Banding / Ringing type artifacts?

Carbon bikes do not have bare carbon exposed to the outside. Most likely it’s about preserving prints and lacquer. Carbon fibers and epoxy they are made from shouldn’t be affected by IPA.

Right, but look at my picture. At that low speed, the VFA is awful. The suggestion to boost speed to avoid VFA is incompatible with printing shiny silk.

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Have you already tried to simply place the printer on the ground for a testprint? Sometimes these kind of artifacts simply appear from a wobbly surface or resonance compensation feet.
I would test it right on the floor without any extra dampening and see if that helps.

I have really no clue of what are causing you this artifact, especially with PLA wich often works great.

Anyways I reallize that this thread have turned to talk only on VFA, that’s why you should open your own topic, and give as much information as you can in your first post.

About VFA, Prusa have resolved this problem (visible on MK3) ont their new MK4 by using 0.9° stepper motors, so maybe this is only related to stepper motors used in Bambu printer

Could it be that the better stepper motors are more expensive? I myself work in a company that manufactures frequency converters. Here, even with the smallest fan, every cent is turned over 3 times. The main thing is that the components are cheap and the margin increases. Surely it’s no different here in our case - the majority of customers are satisfied with the printer, so why should the manufacturer change anything?

Of course, I don’t know if that’s the case, but it seems reasonable to assume that it is. :frowning:

This needs to be un-flagged as solved since it is still happening after the post 195 for some, and the hunt for the squareness of the carriage is under scrutiny.

Anyhow - this issue will be an ongoing thing for a while. We thought long and hard on the smooth pulley, then someone finally did a test and disproved that one.

Then it was a calibration thing, kind of helped but not a cure

Now, as mentioned above squareness and belt tension is the target.

Someone will get around to a stepper motor change (this printer does not like TL smoothers at all, which should have worked - caused a feedback loop and the carriage sit and vibrate). Wondering if it is running on a PWM.

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Changing the steppers to .9 degree will also require some additional start Gcode to set X/Y steps, but as with people trying to “calibrate” for dimensions, you have no way to know what the current values are. That said, for my Prusa, .9 steppers definitely help with VFAs (hence Prusa switching to them for the MK4.)

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Currently for a print going, using PETG. I placed the part at 45 degrees on the bed. The long sides of the print are clearly showing the worst VFA’s I’ve seen on my printer. I’m wondering if the orientation means only one stepper is driving the position of the tool head? If my understanding of core XY is correct? Would they explain why I’m seeing the VFA’s? The PETG doesn’t help as it’s quite shiny

Maybe someone can invent a tool for checking x square to y.
Something that has a little notch for both axis so you dont need have four arms to held a rightangle to the steelrods.

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I second that. Having a x/y tool for checking square seems to me like it’s a must have. Just another issue that’s popping up with these machines.

https://www.printables.com/model/454352-p1p-90-degree-x-and-y-axis-holder-jig

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Only thing is that if you print this object on the BL which you suspect not having square X Y axis, the resulting model will also not be really square…

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Possibly. But I think it prints upright so would be less prone to that. I am going to print one and check the angle independently. I think it will also work on the X1C, but we’ll see.

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Printed one of those jigs and measured it - came in at exactly 90 degrees. It also fits the X1/X1C, as I expected.

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Now to see if it gets rid of the ghosting, see the first 50 posts for sample files

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I have not seen the sort of ghosting others have.

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Seems to be related:

That does look a lot worse than either of my printers. The only silk I have is a tri-color; I might print a VFA with that to try to accentuate the artifact though it might end up looking a bit strange in other ways. I usually up the print temperature on most PLAs to maintain a shine at high temp, but that depends a lot on brand. My usual stuff I print at 240C, and I suspect you can go higher. I would recommend always printing with the cool plate if possible, since the lower chamber temperature can help reduce the likelihood of heat creep.

I have some horrible ideas that would give a few of the motion control engineers a heart attack, but they may help if you’re primarily targeting low speed prints.

At this point I actually think this might be characteristic of ALL printers. Note that we are NOT talking about z-wobble. paykoman84 / frank.d, that doesn’t look that great but this thread is about waviness in the other direction - VFA / ringing artifacts are waviness back and forth or left and right, not up and down (in XY not in Z). The crazy thing I’m going to tell you is you should try turning down the speed and see if the z-wobbliness goes away (could be due to insufficient cooling)

What about using these motors?

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I printed one too. The fact it tries to clip onto all the rods seems like a design flaw. I was wanting to use it to confirm I was at 90 degrees but the side rod being hidden inside a groove meant I can’t easily see that. I’d rather it just had a flat surface on that side so I can see if the side rod is perfectly parallel.

Clipping onto the carbon rods the way it does also got me worried I might scratch them accidentally. I don’t think it will but given those aren’t sensibly replaceable that’s definitely a concern to me.